Low expression of collagen receptors in moderate and poorly differentiated colorectal adenocarcinomas.
Low expression of collagen receptors in moderate and poorly differentiated colorectal adenocarcinomas.
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DOI：
10.1038/bjc.1990.141
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发表时间：
1990-04
影响因子：
8.8
通讯作者：
Bodmer, W F
中科院分区：
文献类型：
--
作者：
Pignatelli, M;Smith, M E;Bodmer, W F
胶原蛋白是细胞外基质（ECM）的主要成分，并且可以影响上皮细胞的极性、增殖和分化（Reddi，1984）。最近在各种正常和转化细胞上鉴定了胶原和其它ECM蛋白的特异性受体（Hemler，1988; Wayner和Carter，1987）。这些受体可以通过充当胶原基质和细胞骨架之间的信号转导子来介导胶原对细胞增殖和分化的作用（Bissell等人，1982年）。我们最近已经表明，培养的结肠肿瘤细胞对胶原蛋白的分化信号变得无反应，并获得不受控制的生长模式，部分原因是特定细胞表面胶原蛋白受体的丢失（Pignatelli和Bodmer，1988）。我们现在有初步的证据表明，所描述的胶原受体属于ECM受体的整合蛋白家族，其是分为三个亚家族（P1，P2，P3，P4，P5，P6，P8）的异二聚体跨膜蛋白。和P3）基于共享共同的P链（Hynes，1987; Ruoslahti & Piershbacher，1987）。至少两种整联蛋白胶原蛋白受体VLA-2（2011）和VLA-3（03 p），其特征在于亲和层析和特异性单克隆抗体抑制细胞与胶原蛋白的粘附（Wayner &Carter，1987），通常由上皮细胞表达（Wayner等人，1988年）。因此，这些和其他类似受体的缺乏可能在肿瘤细胞中被强烈选择，它们的丢失可能构成向未分化生长模式的主要步骤（Bodmer，1988）。在此，我们报道了显示两种已知的整合素胶原蛋白受体VLA-2和VLA-3的α 3链以及α 2和α 3链分别进行性丢失的数据（Wayner & Carter，1987; Wayner et al.，1988），与结肠直肠腺癌患者的肿瘤分化丧失相关。从四个腺瘤，24结直肠腺癌和相邻的宏观正常结肠粘膜（10厘米，从原发性肿瘤）的冷冻切片进行染色的间接免疫过氧化物酶技术使用的DH 12，B1。515和E1。56种小鼠单克隆抗体。在蛋白质印迹、免疫沉淀和免疫组织化学中，DH 12与人PI整联蛋白链反应（De Strooper等人，1988年，1989年），是一个慷慨的礼物博士巴特德斯特罗珀（鲁汶大学，比利时）。其作为腹水获得，并以20 μ g/ml浓度在磷酸盐缓冲盐水（PBS）中使用。B1. 515与人VLA-2和E1的α 2链反应。56与人VLA-3的α 3链通过免疫沉淀和免疫荧光化学（Pischel等，1987年，1988年）。B1. 515和E1。56种单克隆抗体是Ken Pischel博士（美国圣地亚哥加州大学）的慷慨馈赠。都是B1 515和E1。56以纯化形式获得，用PBS稀释并以20 μ g/ml浓度使用。将冷冻切片（61 μ m）在丙酮中固定10分钟，然后在PBS中洗涤。然后将切片与20 μ l的每种单克隆抗体在加湿室中孵育60分钟，在PBS中洗涤三次并孵育10分钟。
Collagens are major componentsof the extracellular matrix (ECM) and can influence polarity, proliferation and differentiation of epithelial cells (Reddi, 1984). Specific recep-tors for collagens and other ECM proteins have recently been identified on various normal and transformed cells (Hemler, 1988; Wayner and Carter, 1987). These receptors may mediate the effects of collagens on cell proliferation and differentiation by acting as transducers of signals between the collagen matrix andthe cytoskeleton (Bissell et al., 1982). We have recently shown that colon tumour cells in culture become unresponsive to the differentiating signals of collagen and acquire an uncontrolled pattern of growth, due in part to loss of a specific cell surface collagen receptor (Pignatelli & Bodmer, 1988). We now have preliminary evidence suggesting that the collagen receptor described belongs to the inte-grin family of ECM receptors which are axp heterodimeric transmembrane proteins divided into three subfamilies (PI, P2. and P3) based on the sharing of a common P chain (Hynes, 1987; Ruoslahti & Piershbacher, 1987). At least two integrin collagen receptors, VLA-2 (2011) and VLA-3 (03p), charac-terised by affinity chromatography and by inhibition of cell adhesion to collagen by specific monoclonal antibodies (Wayner &Carter, 1987), are normally expressed by epithelial cells (Wayner et al., 1988). Lack of these and other similar receptors could therefore be strongly selected for in tumour cells and their loss could constitute major steps towards an indifferentiated pattern of growth (Bodmer, 1988). Here we report data showing a progressive loss of the 13 chain and of the a2 and o3 chains of the two known integrin collagen receptors VLA-2 and VLA-3 respectively (Wayner & Carter, 1987; Wayner et al., 1988), associated with a loss of tumour differentiation in patients with colorectal adenocarcinoma. Cryostat sections from four adenomas, 24 colorectal adenocarcinomas and the adjacent macroscopically normal colonic mucosa (10 cm from the primary tumour) were stained by an indirect immunoperoxidase technique using the DH12, B1. 515 and E1. 56 mouse monoclonal antibodies. DH12 reacts with the human PI integrin chain in western blot, immunoprecipitation and immunohistochemistry (De Strooper et al., 1988, 1989) and was a generous gift of Dr Bart De Strooper (University of Leuven, Belgium). It was obtained as ascites fluid and used at 20 jg ml-'concentration in phosphate bufferedsaline (PBS). B1. 515 reacts with the a2 chain of human VLA-2 and E1. 56 with the a3 chain of human VLA-3 by immunoprecipitation and immunohisto-chemistry (Pischel et al., 1987, 1988). B1. 515 and E1. 56 monoclonal antibodies were a generous gift of Dr Ken Pischel (University of California, San Diego, USA). Both B1. 515 and E1. 56 were obtained in purified form, diluted with PBS and used at 20 g ml-'concentration. Cryostat sections (61im) were fixed in acetone for 10min and then washed in PBS. Sections were then incubated with 20 l of each monoclonal antibody for60min in a humidified chamber, washed three times in PBS and incubated for